1. Field of the Invention
This invention relates to a dry-type analytical element for the analysis of albumin, and more particularly, relates to an integral multilayer analytical element being dry operative for the quantitative analysis of albumin in biological body fluids, such as blood, cerebrospinal fluid, saliva, lymph and urine.
2. Background of the Invention
It is known that tha albumin in biological body fluids, such as blood, cerebrospinal fluid, saliva, lymph and urine, can be measured or determined by using a buffered Bromocresol Green (BCG) solution or a test piece disclosed in U.S. Pat. Nos. 3 533 749 or 3 485 587 according to the principle of colorimetry. BCG is one of acid-base indicator belonging to sulfonphthalein dyes.
Acid base indicators such as BCG are not specific for albumin. The globulin, transferrin and other proteins existing in human body fluid competes with albumin to bind to acid-base indicator, and give an error in the measured value. The above competitive inhibition is particularly remarkable in a low concentration of albumin. The total protein concentrations of human sera are usually in the range of about 6 to 8 g/dl. Globulin concentration in the total protein is usually about 2.9 g/dl, and the remainder is mainly albumin. The competitive inhibition appears in the above albumin concentration.